Such a compensating device for a fibrous nonwoven is known from EP 1 643 022 B1. It is arranged between a nonwoven laying device and a needle machine and has an endless, rotatingly driven storage belt with two deflecting rollers. The fibrous nonwoven is arranged on the upper run of the storage belt and stored temporarily in a variable slack of the upper run as needed. Differences in speed between the nonwoven laying device and the needle machine can be compensated hereby. The amount of the slack and the size of the nonwoven storage device is determined by differences in the speed of the drives at the deflecting rollers.